E 300D (210.020) L6-3.0L DSL (606.912) (1996)
Oxygen Sensor: Locations
O2 Sensor 2 (After TWC) - G3/1
Under car, after catalytic converter
O2S 1 (Before TWC) - G3/2
Under car, above and in front of catalytic converter
O2S 1 (Before TWC), Left - G3/3
Under car, on exhaust pipe at left of engine
O2S 1 (Before TWC), Right - G3/4